CHIOS, XIO, or Scio, an Asiatic island, lying near the coast of Ionia, in Natolia or Lesser Asia, about one hundred miles west of Smyrna. It is called by the Turks Sakifaduci, and is about one hundred miles in circumference; being chiefly inhabited by Christians of the Greek church, who are said to have three hundred churches in the island.

CHIO is also the capital of the above island, situated on the east coast: E. long. 27°, and N. lat. 38°.